BEIJING (AFP): A knifeman stabbed three children to death and wounded five more plus a teacher in a rampage Monday at a Chinese primary school that refused to enrol his daughter, reports said.The attacker killed himself by jumping from a building following the carnage at a school in Shiyan in the central province of Hubei, according to the official news agency Xinhua. The six wounded have been hospitalised, it said, adding two were seriously hurt. The man, surnamed Chen, “died on the spot”, Xinhua said without providing further details. “An initial probe suggests Chen held a grudge after his daughter was denied registration into the new semester’s courses for not completing her summer vocation homework,” the news agency added, citing police. A local police official declined to provide information, saying: “I am not clear, the police bureau officials are at that school investigating.”Monday was the first day of the new school year in many parts of China.Xinhua said it was not immediately known how Chen entered the premises, adding: “Security at many schools has been tightened after a spate of attacks on children in recent years.”They include five incidents in 2010 that killed 17 people - 15 of them children - and wounded more than 80.Last March a man killed two relatives and then slashed 11 people, including six children, outside a school in China’s commercial hub Shanghai.Earlier this summer police in Qianjing - which is near Shiyan - killed a suspect who was attempting to take over a primary school, state media said.